[Intel-gfx] [PATCH 3/4] drm/i915: Enabling pre-multiplied alpha drm property

[Damien Lespiau]

On Thu, Mar 20, 2014 at 02:51:20PM +0100, Daniel Vetter wrote:
> I don't really have a decent opinion on the pre-multiplied vs
> non-premultiplied ARGB formats issue at hand. In case of doubt I think we
> should follow what gl does. But I have no clue how that's handled in gl
> ;-)
 
I'd still like a premultipled DRM format, but let's wait for Ville
opinion.

In GL, the blending equation doesn't do anything automatically. So if
you have a premultiplied source, you need to setup the blending
function/factor accordingly.

-- 
Damien